Results 61 to 70 of about 5,513 (178)

Remarkable electronic effect on the total stereoselectivity of the cycloaddition reaction of arylnitrile oxides with pyrrol-2-one derivatives

Heterocyclic Communications, 2019
The regiospecific 1,3-dipolar cycloaddition of 1,5-dihydropyrrol-2-one and arylnitrile oxides derivatives have been investigated. The asymmetric induction expected by the chiral centre of the 5-hydroxy-3-methyl-1,5-dihydropyrrol-2-one derivatives was ...
Guesmi A, Hamadi N Ben
doaj   +1 more source

Synthesis of Spiroisoxazolines by 1,3-Dipolar Cycloaddition

Molecules, 1997
The cycloaddition of the chiral nitrile oxide 1 to 1-R-substituted 3,3-methylene-5,5-dimethyl-2-pyrrolidinones 2 (where R is H, n-butyl-, 1,1-dimethylethoxycarbonyl-, 1-methylethenyl- and acetyl-) proceeds regioselectively under the formation of ...
Peter Ertl, Vladimír Ondrus, Lubor Fisera, Peter Micuch   +3 more
doaj   +1 more source

Enantioselective Cycloaddition Reactions Catalyzed by BINOL-Derived Phosphoric Acids and N-Triflyl Phosphoramides: Recent Advances

Molecules, 2015
Over the last several years there has been a huge increase in the development and applications of new efficient organocatalysts for enantioselective pericyclic reactions, which represent one of the most powerful types of organic transformations.
Felix E. Held, Dominik Grau, Svetlana B. Tsogoeva   +2 more
doaj   +1 more source

Green ultrasound-assisted three-component click synthesis of novel 1H-1,2,3-triazole carrying benzothiazoles and fluorinated-1,2,4-triazole conjugates and their antimicrobial evaluation

Acta Pharmaceutica, 2017
The present study describes an efficient and ecofriendly, ultrasound, one-pot click cycloaddition approach for the construction of a novel series of 1,4-disubstituted-1,2,3-triazoles tethered with fluorinated 1,2,4-triazole-benzothiazole molecular ...
Rezki Nadjet, Aouad Mohamed Reda
doaj   +1 more source

Cycloaddition Reactions of C,N-Diphenylnitrone to Methylene-γ-butyrolactones

Molecules, 2000
Cycloaddition of C,N-diphenylnitrone to α-methylene-γ-butyrolactone afforded two diastereomeric 5-spirosubstituted isoxazolidines with high selectivity.
Andrea Goti, Cristina Faggi, Franca M. Cordero, Martina Cacciarini   +3 more
doaj   +1 more source

Synthesis and In Silico Analysis of New Polyheterocyclic Molecules Derived from [1,4]-Benzoxazin-3-one and Their Inhibitory Effect against Pancreatic α-Amylase and Intestinal α-Glucosidase

Molecules
This study focuses on synthesizing a new series of isoxazolinyl-1,2,3-triazolyl-[1,4]-benzoxazin-3-one derivatives 5a–5o. The synthesis method involves a double 1,3-dipolar cycloaddition reaction following a “click chemistry” approach, starting from the ...
Mohamed Ellouz, Aziz Ihammi, Abdellah Baraich, Ayoub Farihi, Darifa Addichi, Saliha Loughmari, Nada Kheira Sebbar, Mohamed Bouhrim, Ramzi A. Mothana, Omar M. Noman, Bruno Eto, Fatiha Chigr, Mohammed Chigr   +12 more
doaj   +1 more source

Reaction of Nitrilimines with Pyruvaldehyde Hydrazones: Synthesis and Antimicrobial Evaluation of Some New 1,2,4-Triazole Derivatives

Journal of Chemistry, 2015
A new series of 1,3,4,5,5-pentasubstituted-1,2,4-triazoles (4a–j, 6a–j) have been synthesized by the 1,3-dipolar cycloaddition of suitable nitrilimines 2 to pyruvaldehyde (2-oxopropanal) hydrazones having (COPh, COOMe, COOEt, Me/Me, and Me/Ph) groups 3 ...
Hany M. Dalloul
doaj   +1 more source

A Novel One-Pot Green Synthesis of Dispirooxindolo-pyrrolidines via 1,3-Dipolar Cycloaddition Reactions of Azomethine Ylides

Molecules, 2015
A facile synthesis of dispirooxindolopyrrolidines has been accomplished via a one-pot three component 1,3-dipolar cycloaddition reaction. The reaction of azomethine ylides generated in situ from L-phenylalanine and substituted isatins with a series of ...
Abdulrahman I. Almansour, Natarajan Arumugam, Raju Suresh Kumar, Govindasami Periyasami, Hazem A. Ghabbour, Hoong-Kun Fun   +5 more
doaj   +1 more source

Studies on Heterocyclic Compounds. XIV. 1, 3-Dipolar Cycloaddition Reaction of Dimethyl Acetylenedicarboxylate with Phenylhydrazones

Chemical and Pharmaceutical Bulletin, 1973
1, 3-Dipolar cycloaddition of aldehyde hydrazones with dimethyl acetylenedicarboxylate without solvent gives rise to dimethyl 1, 3-diphenylpyrazole-4, 5-dicarboxylate, and in some cases trimethyl 1-phenylpyrazole-3, 4, 5-tricarboxylate as a by-product.
OGURA, HARUO, KUBO, KAZUO, WATANABE, YUMIKO, ITOH, TSUNEO   +3 more
openaire   +2 more sources

Convenient Synthesis and Biological Evaluation of Modafinil Derivatives: Benzhydrylsulfanyl and Benzhydrylsulfinyl [1,2,3]triazol-4-yl-methyl Esters

Molecules, 2011
Simple synthesis and biological activities of modafinil derivatives are described. The key reactions include condensation of acid and propargyl alcohol, subsequent 1,3-dipolar cycloaddition reaction of alkynes and (3-azido-propyl)cyclohexane or (4-azido ...
Seikwan Oh, Mankil Jung, Eunyoung Lim, Jee-Young Son, Yeonju Lee, Jae-Chul Jung   +5 more
doaj   +1 more source